mybatis实现对数据的增删查改实例详解

package com.edu.hpu.domain; 
/** 
* @author administrator 
*user表所对应的实体类 
*/ 
public class user { 
//实体类的属性和表的字段名称一一对应 
private int id; 
private string name; 
private int age; 
//对属性进行封装 
public int getid() { 
return id; 
} 
public void setid(int id) { 
this.id = id; 
} 
public string getname() { 
return name; 
} 
public void setname(string name) { 
this.name = name; 
} 
public int getage() { 
return age; 
} 
public void setage(int age) { 
this.age = age; 
} 
//添加tostring方法 
@override 
public string tostring() { 
return "user [id=" + id + ",name=" + name + ",age=" + age + "]"; 
} 
} 

package com.edu.hpu.util; 
import java.io.inputstream; 
import org.apache.ibatis.session.sqlsession; 
import org.apache.ibatis.session.sqlsessionfactory; 
import org.apache.ibatis.session.sqlsessionfactorybuilder; 
public class mybatisutil { 
/** 
* 获取sqlsessionfactory 
* @return sqlsessionfactory 
*/ 
public static sqlsessionfactory getsqlsessionfactory() { 
string resource = "conf.xml";//调取配置文件 
inputstream is = mybatisutil.class.getclassloader().getresourceasstream(resource); 
sqlsessionfactory factory = new sqlsessionfactorybuilder().build(is); 
return factory; 
} 
/** 
* 获取sqlsession 
* @return sqlsession 
*/ 
public static sqlsession getsqlsession() { 
return getsqlsessionfactory().opensession(); 
} 
/** 
* 获取sqlsession 
* @param isautocommit 
* true 表示创建的sqlsession对象在执行完sql之后会自动提交事务 
* false 表示创建的sqlsession对象在执行完sql之后不会自动提交事务，这时就需要我们手动调用sqlsession.commit()提交事务 
* @return sqlsession 
*/ 
public static sqlsession getsqlsession(boolean isautocommit) { 
return getsqlsessionfactory().opensession(isautocommit); 
} 
} 

<?xml version="1.0" encoding="utf-8"?> 
<!doctype configuration public "-//mybatis.org//dtd config 3.0//en" "http://mybatis.org/dtd/mybatis-3-config.dtd"> 
<configuration> 
<environments default="development"> 
<environment id="development"> 
<transactionmanager type="jdbc" /> 
<!-- 配置数据库连接信息 --> 
<datasource type="pooled"> 
<property name="driver" value="com.mysql.jdbc.driver" /> 
<property name="url" value="jdbc:mysql://localhost:3306/test?useunicode=true&characterencoding=utf-8&zerodatetimebehavior=converttonull" /> 
<property name="username" value="root" /> 
<property name="password" value="admin" /> 
</datasource> 
</environment> 
</environments> 
<mappers> 
<!-- 注册usermapper.xml文件， 
usermapper.xml位于com.edu.hpu.mapping这个包下，所以resource写成com/edu/hpu/mapping/usermapper.xml--> 
<mapper resource="com/edu/hpu/mapping/usermapper.xml"/> 
<!-- <mapper class="com.edu.hpu.mapping.usermapper_11"/> --> 
</mappers> 
</configuration> 

<?xml version="1.0" encoding="utf-8" ?> 
<!doctype mapper public "-//mybatis.org//dtd mapper 3.0//en" "http://mybatis.org/dtd/mybatis-3-mapper.dtd"> 
<mapper namespace="com.edu.hpu.mapping.usermapper"> 
<!-- 在select标签中编写查询的sql语句， 设置select标签的id属性为getuser，id属性值必须是唯一的，不能够重复 
使用parametertype属性指明查询时使用的参数类型，resulttype属性指明查询返回的结果集类型 
resulttype="com.edu.hpu.domain.user"就表示将查询结果封装成一个user类的对象返回 
user类就是users表所对应的实体类 
--> 
<!-- 
根据id查询得到一个user对象 
--> 
<select id="getuser" parametertype="int" 
resulttype="com.edu.hpu.domain.user"> 
select * from users where id=#{id} 
</select> 
<!-- 创建用户(create) --> 
<insert id="adduser" parametertype="com.edu.hpu.domain.user"> 
insert into users(name,age) values(#{name},#{age}) 
</insert> 
<!-- 删除用户(remove) --> 
<delete id="deleteuser" parametertype="int"> 
delete from users where id=#{id} 
</delete> 
<!-- 修改用户(update) --> 
<update id="updateuser" parametertype="com.edu.hpu.domain.user"> 
update users set name=#{name},age=#{age} where id=#{id} 
</update> 
<!-- 查询全部用户--> 
<select id="getallusers" resulttype="com.edu.hpu.domain.user"> 
select * from users 
</select> 
</mapper> 

package com.edu.hpu.test; 
import java.util.list; 
import com.edu.hpu.domain.user; 
import com.edu.hpu.util.mybatisutil; 
import org.junit.test; 
import org.apache.ibatis.session.sqlsession; 
public class test2 { 
@test 
public void testadd(){ 
//sqlsession sqlsession = mybatisutil.getsqlsession(false); 
sqlsession sqlsession = mybatisutil.getsqlsession(true); 
/** 
* 映射sql的标识字符串， 
* com.edu.hpu.mapping.usermapper是usermapper.xml文件中mapper标签的namespace属性的值， 
* adduser是insert标签的id属性值，通过insert标签的id属性值就可以找到要执行的sql 
*/ 
string statement = "com.edu.hpu.mapping.usermapper.adduser";//映射sql的标识字符串 
user user = new user(); 
user.setname("新增用户小黄"); 
user.setage(20); 
//执行插入操作 
int retresult = sqlsession.insert(statement,user); 
//手动提交事务 
//sqlsession.commit(); 
//使用sqlsession执行完sql之后需要关闭sqlsession 
sqlsession.close(); 
system.out.println(retresult); 
} 
@test 
public void testupdate(){ 
sqlsession sqlsession = mybatisutil.getsqlsession(true); 
/** 
* 映射sql的标识字符串， 
* com.edu.hpu.mapping.usermapper是usermapper.xml文件中mapper标签的namespace属性的值， 
* updateuser是update标签的id属性值，通过update标签的id属性值就可以找到要执行的sql 
*/ 
string statement = "com.edu.hpu.mapping.usermapper.updateuser";//映射sql的标识字符串 
user user = new user(); 
user.setid(3); 
user.setname("hello world"); 
user.setage(25); 
//执行修改操作 
int retresult = sqlsession.update(statement,user); 
//使用sqlsession执行完sql之后需要关闭sqlsession 
sqlsession.close(); 
system.out.println(retresult); 
} 
@test 
public void testdelete(){ 
sqlsession sqlsession = mybatisutil.getsqlsession(true); 
/** 
* 映射sql的标识字符串， 
* com.edu.hpu.mapping.usermapper是usermapper.xml文件中mapper标签的namespace属性的值， 
* deleteuser是delete标签的id属性值，通过delete标签的id属性值就可以找到要执行的sql 
*/ 
string statement = "com.edu.hpu.mapping.usermapper.deleteuser";//映射sql的标识字符串 
//执行删除操作 
int retresult = sqlsession.delete(statement,4); 
//使用sqlsession执行完sql之后需要关闭sqlsession 
sqlsession.close(); 
system.out.println(retresult); 
} 
@test 
public void testgetall(){ 
sqlsession sqlsession = mybatisutil.getsqlsession(); 
/** 
* 映射sql的标识字符串， 
* com.edu.hpu.mapping.usermapper是usermapper.xml文件中mapper标签的namespace属性的值， 
* getallusers是select标签的id属性值，通过select标签的id属性值就可以找到要执行的sql 
*/ 
string statement = "com.edu.hpu.mapping.usermapper.getallusers";//映射sql的标识字符串 
//执行查询操作，将查询结果自动封装成list<user>返回 
list<user> lstusers = sqlsession.selectlist(statement); 
//使用sqlsession执行完sql之后需要关闭sqlsession 
sqlsession.close(); 
system.out.println(lstusers); 
} 
} 

package com.edu.hpu.mapping; 
import java.util.list; 
import com.edu.hpu.domain.user; 
import org.apache.ibatis.annotations.delete; 
import org.apache.ibatis.annotations.insert; 
import org.apache.ibatis.annotations.select; 
import org.apache.ibatis.annotations.update; 
/** 
* @author gacl 
* 定义sql映射的接口，使用注解指明方法要执行的sql 
*/ 
public interface usermapper_11 { 
//使用@insert注解指明add方法要执行的sql 
@insert("insert into users(name, age) values(#{name}, #{age})") 
public int add(user user); 
//使用@delete注解指明deletebyid方法要执行的sql 
@delete("delete from users where id=#{id}") 
public int deletebyid(int id); 
//使用@update注解指明update方法要执行的sql 
@update("update users set name=#{name},age=#{age} where id=#{id}") 
public int update(user user); 
//使用@select注解指明getbyid方法要执行的sql 
@select("select * from users where id=#{id}") 
public user getbyid(int id); 
//使用@select注解指明getall方法要执行的sql 
@select("select * from users") 
public list<user> getall(); 
} 

<mapper class="com.edu.hpu.mapping.usermapper_11"/>

package com.edu.hpu.test; 
import java.util.list; 
import com.edu.hpu.domain.user; 
import com.edu.hpu.mapping.usermapper_11; 
import com.edu.hpu.util.mybatisutil; 
import org.apache.ibatis.session.sqlsession; 
import org.junit.test; 
/** 
* @author administrator 
*对注解进行测试 
*/ 
public class test3 { 
@test 
public void testadd(){ 
sqlsession sqlsession = mybatisutil.getsqlsession(true); 
//得到usermapper接口的实现类对象，usermapper接口的实现类对象由sqlsession.getmapper(usermapper.class)动态构建出来 
usermapper_11 mapper = sqlsession.getmapper(usermapper_11.class); 
user user = new user(); 
user.setname("大智若愚"); 
user.setage(20); 
int add = mapper.add(user); 
//使用sqlsession执行完sql之后需要关闭sqlsession 
sqlsession.close(); 
system.out.println(add); 
} 
@test 
public void testupdate(){ 
sqlsession sqlsession = mybatisutil.getsqlsession(true); 
//得到usermapper接口的实现类对象，usermapper接口的实现类对象由sqlsession.getmapper(usermapper.class)动态构建出来 
usermapper_11 mapper = sqlsession.getmapper(usermapper_11.class); 
user user = new user(); 
user.setid(3); 
user.setname("大音希声"); 
user.setage(26); 
//执行修改操作 
int retresult = mapper.update(user); 
//使用sqlsession执行完sql之后需要关闭sqlsession 
sqlsession.close(); 
system.out.println(retresult); 
} 
@test 
public void testdelete(){ 
sqlsession sqlsession = mybatisutil.getsqlsession(true); 
//得到usermapper接口的实现类对象，usermapper接口的实现类对象由sqlsession.getmapper(usermapper.class)动态构建出来 
usermapper_11 mapper = sqlsession.getmapper(usermapper_11.class); 
//执行删除操作 
int retresult = mapper.deletebyid(7); 
//使用sqlsession执行完sql之后需要关闭sqlsession 
sqlsession.close(); 
system.out.println(retresult); 
} 
@test 
public void testgetuser(){ 
sqlsession sqlsession = mybatisutil.getsqlsession(); 
//得到usermapper接口的实现类对象，usermapperi接口的实现类对象由sqlsession.getmapper(usermapper.class)动态构建出来 
usermapper_11 mapper = sqlsession.getmapper(usermapper_11.class); 
//执行查询操作，将查询结果自动封装成user返回 
user user = mapper.getbyid(1); 
//使用sqlsession执行完sql之后需要关闭sqlsession 
sqlsession.close(); 
system.out.println(user); 
} 
@test 
public void testgetall(){ 
sqlsession sqlsession = mybatisutil.getsqlsession(); 
//得到usermapper接口的实现类对象，usermapper接口的实现类对象由sqlsession.getmapper(usermapper.class)动态构建出来 
usermapper_11 mapper = sqlsession.getmapper(usermapper_11.class); 
//执行查询操作，将查询结果自动封装成list<user>返回 
list<user> lstusers = mapper.getall(); 
//使用sqlsession执行完sql之后需要关闭sqlsession 
sqlsession.close(); 
system.out.println(lstusers); 
} 
}